See also:

Lane Change Warning System monitors vehicles following behind
Inattentiveness or misjudgement of the distance and speed of a vehicle approaching from behind can lead the driver into a critical situation when changing lanes. The optional Lane Change Warning S ...

ConnectedDrive or BMW Assist
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Convertible: rollover protection system
The rollover protection system is activated automatically in the event of an accident, a critical driving situation, an extreme tilt in the car's longitudinal axis or upon loss of ground conta ...